[Bf-blender-cvs] [3aba11c82e] temp-cycles-denoising: Cycles: Experiment with shadow catcher
Sergey Sharybin
noreply at git.blender.org
Mon Feb 13 02:05:56 CET 2017
Commit: 3aba11c82e087404656d93f957848f436775b805
Author: Sergey Sharybin
Date: Sun Feb 12 03:17:48 2017 +0100
Branches: temp-cycles-denoising
https://developer.blender.org/rB3aba11c82e087404656d93f957848f436775b805
Cycles: Experiment with shadow catcher
**DISCLAIMER**: This is more a code dump of a local branch, not somewhat really finished or so. Underlying math is the subject for rework since it's not quite physically based at all.
Publishing to start collaboration with other Cycles developers who are looking into solving this puzzle.
=== What do we consider a shadow catcher? ===
That's a good question actually, and there's no single formulation of what it exactly is and mathematically it's a bit malformed in the constraints we're working on. Ideally shadow catcher is a difference between image rendered without artificial objects and with them. Such approach gives best ever shadows, but takes 2x more time to render. So for good usability we need to get some assumptions, make system a bit more biased but give artists an useful tool.
Shadow catcher is mainly used by VFX artists to inject artificial objects into real footage. At least that definition we'll stick to
in Blender. Hence here's what shadow catcher should be capable of doing:
- Receive shadows from other objects: be totally transparent when there's no shadows cast on it, be more opaque in shaded areas.
- Ignore self-shadowing and shading. Shadows caused by occlusion with itself already exists in the footage. Same applies to the
shading -- all shading caused by material itself are also in the footage already.
- Interact with other objects in the scene. This sounds a bit tricky but makes sense actually. Consider situation when one needs to put sharp glossy object into the footage: you'll want objects from a real scene to be reflected in the artificial object. And often you'll want the object on which shadow is to be cast to be reflected in such situations. Surely you can escape with copying object and playing with ray visibility, but that's complicated scene setup instead of making it simpler.
- Be affected with indirect light. Cycles is the GI render engine after all!
=== How to use the shadow catcher? ===
1. Create an object on which you want to receive shadow.
2. Create some basic material setup which is close to a real object.
3. Enable "Shadow Catcher" in Object buttons -> Cycles Settings.
4. Be happy! (hopefully, once we've debugged all the code)
=== What this patch actually contains? ===
It contains all the bits which tries to implement definition of shadow catcher above. It is trying to implement it all in a way so we don't need to make big changes in the ray integration loop, hence it has some tricky magic to deduct what was the received shadow from the light passes and will fail in certain situations, mainly when there is no direct lighting of the object at all. It is totally tweakable to become more artists friendly, i just didn't have enough time to try all the ideas [...]
Major changes are in fact made around shadow_blocked() to exclude shading from self. This part is based on an older patch which tried to expose it to an user. That exposing settings are somewhat malformed and shouldn't really be used. In fact, we should remove those settings from the interface.
=== Some pictures? ===
Sure, here's one from a hackish patch:
{F282085}
(This is a glossy monkey on a checker board floor, floor is makred as a catcher, Here's .blend file {F282088})
Reviewers: lukasstockner97, juicyfruit, brecht
Subscribers: jensverwiebe, Nikos_prinio, brecht, lukasstockner97, borisdonalds, aliasguru, YAFU, forest-house, uli_k, aditiapratama, hype, davidandrade, printerkiller, jta, Davd, johnroper100, poor, lowercase, juang3d, GiantCowFIlms, iklsr, gandalf3, sasa42, saphires, duarteframos, madog, Lapineige, railla, zuggamasta, plasmasolutions, jesterking
Differential Revision: https://developer.blender.org/D1788
===================================================================
M intern/cycles/blender/addon/properties.py
M intern/cycles/blender/addon/ui.py
M intern/cycles/blender/blender_object.cpp
M intern/cycles/kernel/bvh/bvh.h
M intern/cycles/kernel/bvh/bvh_shadow_all.h
M intern/cycles/kernel/bvh/qbvh_shadow_all.h
M intern/cycles/kernel/kernel_accumulate.h
M intern/cycles/kernel/kernel_path.h
M intern/cycles/kernel/kernel_path_branched.h
M intern/cycles/kernel/kernel_path_state.h
M intern/cycles/kernel/kernel_path_surface.h
M intern/cycles/kernel/kernel_shader.h
M intern/cycles/kernel/kernel_shadow.h
M intern/cycles/kernel/kernel_types.h
M intern/cycles/kernel/split/kernel_background_buffer_update.h
M intern/cycles/render/object.cpp
M intern/cycles/render/object.h
===================================================================
diff --git a/intern/cycles/blender/addon/properties.py b/intern/cycles/blender/addon/properties.py
index 5c51f9afc2..df0592a871 100644
--- a/intern/cycles/blender/addon/properties.py
+++ b/intern/cycles/blender/addon/properties.py
@@ -1092,6 +1092,12 @@ class CyclesObjectSettings(bpy.types.PropertyGroup):
default=1.0,
)
+ cls.is_shadow_catcher = BoolProperty(
+ name="Shadow Catcher",
+ description="This object is only catching shadows",
+ default=False,
+ )
+
@classmethod
def unregister(cls):
del bpy.types.Object.cycles
diff --git a/intern/cycles/blender/addon/ui.py b/intern/cycles/blender/addon/ui.py
index 44af5f7efe..5c906d55fd 100644
--- a/intern/cycles/blender/addon/ui.py
+++ b/intern/cycles/blender/addon/ui.py
@@ -799,6 +799,9 @@ class CyclesObject_PT_cycles_settings(CyclesButtonsPanel, Panel):
sub.active = scene.render.use_simplify and cscene.use_distance_cull
sub.prop(cob, "use_distance_cull")
+ col = layout.column()
+ col.prop(cob, "is_shadow_catcher")
+
class CYCLES_OT_use_shading_nodes(Operator):
"""Enable nodes on a material, world or lamp"""
diff --git a/intern/cycles/blender/blender_object.cpp b/intern/cycles/blender/blender_object.cpp
index 637cf7abda..968861391a 100644
--- a/intern/cycles/blender/blender_object.cpp
+++ b/intern/cycles/blender/blender_object.cpp
@@ -343,6 +343,13 @@ Object *BlenderSync::sync_object(BL::Object& b_parent,
object_updated = true;
}
+ PointerRNA cobject = RNA_pointer_get(&b_ob.ptr, "cycles");
+ bool is_shadow_catcher = get_boolean(cobject, "is_shadow_catcher");
+ if(is_shadow_catcher != object->is_shadow_catcher) {
+ object->is_shadow_catcher = is_shadow_catcher;
+ object_updated = true;
+ }
+
/* object sync
* transform comparison should not be needed, but duplis don't work perfect
* in the depsgraph and may not signal changes, so this is a workaround */
diff --git a/intern/cycles/kernel/bvh/bvh.h b/intern/cycles/kernel/bvh/bvh.h
index 2055746a68..38f01e5b60 100644
--- a/intern/cycles/kernel/bvh/bvh.h
+++ b/intern/cycles/kernel/bvh/bvh.h
@@ -229,30 +229,63 @@ ccl_device_intersect void scene_intersect_subsurface(KernelGlobals *kg,
#endif
#ifdef __SHADOW_RECORD_ALL__
-ccl_device_intersect bool scene_intersect_shadow_all(KernelGlobals *kg, const Ray *ray, Intersection *isect, uint max_hits, uint *num_hits)
+ccl_device_intersect bool scene_intersect_shadow_all(KernelGlobals *kg,
+ const Ray *ray,
+ Intersection *isect,
+ int skip_object,
+ uint max_hits,
+ uint *num_hits)
{
# ifdef __OBJECT_MOTION__
if(kernel_data.bvh.have_motion) {
# ifdef __HAIR__
- if(kernel_data.bvh.have_curves)
- return bvh_intersect_shadow_all_hair_motion(kg, ray, isect, max_hits, num_hits);
+ if(kernel_data.bvh.have_curves) {
+ return bvh_intersect_shadow_all_hair_motion(kg,
+ ray,
+ isect,
+ skip_object,
+ max_hits,
+ num_hits);
+ }
# endif /* __HAIR__ */
- return bvh_intersect_shadow_all_motion(kg, ray, isect, max_hits, num_hits);
+ return bvh_intersect_shadow_all_motion(kg,
+ ray,
+ isect,
+ skip_object,
+ max_hits,
+ num_hits);
}
# endif /* __OBJECT_MOTION__ */
# ifdef __HAIR__
- if(kernel_data.bvh.have_curves)
- return bvh_intersect_shadow_all_hair(kg, ray, isect, max_hits, num_hits);
+ if(kernel_data.bvh.have_curves) {
+ return bvh_intersect_shadow_all_hair(kg,
+ ray,
+ isect,
+ skip_object,
+ max_hits,
+ num_hits);
+ }
# endif /* __HAIR__ */
# ifdef __INSTANCING__
- if(kernel_data.bvh.have_instancing)
- return bvh_intersect_shadow_all_instancing(kg, ray, isect, max_hits, num_hits);
+ if(kernel_data.bvh.have_instancing) {
+ return bvh_intersect_shadow_all_instancing(kg,
+ ray,
+ isect,
+ skip_object,
+ max_hits,
+ num_hits);
+ }
# endif /* __INSTANCING__ */
- return bvh_intersect_shadow_all(kg, ray, isect, max_hits, num_hits);
+ return bvh_intersect_shadow_all(kg,
+ ray,
+ isect,
+ skip_object,
+ max_hits,
+ num_hits);
}
#endif /* __SHADOW_RECORD_ALL__ */
diff --git a/intern/cycles/kernel/bvh/bvh_shadow_all.h b/intern/cycles/kernel/bvh/bvh_shadow_all.h
index df33a86bb1..8c1379c1a1 100644
--- a/intern/cycles/kernel/bvh/bvh_shadow_all.h
+++ b/intern/cycles/kernel/bvh/bvh_shadow_all.h
@@ -45,6 +45,7 @@ ccl_device_inline
bool BVH_FUNCTION_FULL_NAME(BVH)(KernelGlobals *kg,
const Ray *ray,
Intersection *isect_array,
+ const int skip_object,
const uint max_hits,
uint *num_hits)
{
@@ -189,6 +190,16 @@ bool BVH_FUNCTION_FULL_NAME(BVH)(KernelGlobals *kg,
while(prim_addr < prim_addr2) {
kernel_assert((kernel_tex_fetch(__prim_type, prim_addr) & PRIMITIVE_ALL) == p_type);
+#ifdef __SHADOW_TRICKS__
+ uint tri_object = (object == OBJECT_NONE)
+ ? kernel_tex_fetch(__prim_object, prim_addr)
+ : object;
+ if(tri_object == skip_object) {
+ ++prim_addr;
+ continue;
+ }
+#endif
+
bool hit;
/* todo: specialized intersect functions which don't fill in
@@ -400,6 +411,7 @@ bool BVH_FUNCTION_FULL_NAME(BVH)(KernelGlobals *kg,
ccl_device_inline bool BVH_FUNCTION_NAME(KernelGlobals *kg,
const Ray *ray,
Intersection *isect_array,
+ const int skip_object,
const uint max_hits,
uint *num_hits)
{
@@ -408,6 +420,7 @@ ccl_device_inline bool BVH_FUNCTION_NAME(KernelGlobals *kg,
return BVH_FUNCTION_FULL_NAME(QBVH)(kg,
ray,
isect_array,
+ skip_object,
max_hits,
num_hits);
}
@@ -418,6 +431,7 @@ ccl_device_inline bool BVH_FUNCTION_NAME(KernelGlobals *kg,
return BVH_FUNCTION_FULL_NAME(BVH)(kg,
ray,
isect_array,
+ skip_object,
max_hits,
num_hits);
}
diff --git a/intern/cycles/kernel/bvh/qbvh_shadow_all.h b/intern/cycles/kernel/bvh/qbvh_shadow_all.h
index 607295f9ed..fede56bb80 100644
--- a/intern/cycles/kernel/bvh/qbvh_shadow_all.h
+++ b/intern/cycles/kernel/bvh/qbvh_shadow_all.h
@@ -33,6 +33,7 @@
ccl_device bool BVH_FUNCTION_FULL_NAME(QBVH)(KernelGlobals *kg,
const Ray *ray,
Intersection *isect_array,
+ const int skip_object,
const uint max_hits,
uint *num_hits)
{
@@ -270,6 +271,16 @@ ccl_device bool BVH_FUNCTION_FULL_NAME(QBVH)(KernelGlobals *kg,
while(prim_addr < prim_addr2) {
kernel_assert((kernel_tex_fetch(__prim_type, prim_addr) & PRIMITIVE_ALL) == p_type);
+#ifdef __SHADOW_TRICKS__
+ uint tri_object = (object == OBJECT_NONE)
+ ? kernel_tex_fetch(__prim_object, prim_addr)
+ : object;
+ if(tri_object == skip_object) {
+ ++prim_addr;
+ continue;
+ }
+#endif
+
bool hit;
/* todo: specialized intersect functions which don't fill in
diff --git a/intern/cycles/kernel/kernel_accumulate.h b/intern/cycles/kernel/kernel_accumulate.h
index 6c3ee6b809..83fab01dc0 100644
--- a/intern/cycles/kernel/kernel_accumulate.h
+++ b/intern/cycles/kernel/kernel_accumulate.h
@@ -52,10 +52,17 @@ ccl_device_inline void bsdf_eval_init(BsdfEval *eval, ClosureType type, float3 v
{
eval->diffuse = value;
}
+#ifdef __SHADOW_TRICKS__
+ eval->sum_no_mis = make_float3(0.0f, 0.0f, 0.0f);
+#endif
}
-ccl_device_inline void bsdf_eval_accum(BsdfEval *eval, ClosureType type, float3 value)
+ccl_device_inline void bsdf_eval_accum(BsdfEval *eval, ClosureType type, float3 value, float mis_weight)
{
+#ifdef __SHADOW_TRICKS__
+ eval->sum_no_mis += value;
+#endif
+ value *= mis_weight;
#ifdef __PASSES__
if(eval->use_light_pass) {
if(CLOSURE_IS_BSDF_DIFFUSE(type))
@@ -96,7 +103,7 @@ ccl_device_inline bool bsdf_eval_is_zero(BsdfEval *eval)
}
}
-ccl_device_inline void bsdf_eval_mul(BsdfEval *eval, float value)
+ccl_device_inline void bsdf_eval_mis(BsdfEval *eval, float value)
{
#ifdef __PASSES__
if(eval->use_light_pass) {
@@ -115,8 +122,19 @@ ccl_device_inline void bsdf_eval_mul(BsdfEval *eval, float value)
}
}
+ccl_device_inline void bsdf_eval_mul(BsdfEval *eval, float value)
+{
+#ifdef __SHADOW_TRICKS__
+ eval->sum_no_mis *= value;
+#endif
+ bsdf_eval_mis(eval, value);
@@ Diff output truncated at 10240 characters. @@
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